msh: fix "while...continue" bug 3884.

3 files changed, 24 insertions, 0 deletions

diff --git a/shell/msh.c b/shell/msh.c
index 44213c657..eb17eb668 100644
--- a/shell/msh.c
+++ b/shell/msh.c
@@ -2573,6 +2573,10 @@ static int execute(struct op *t, int *pin, int *pout, int no_fork)
                 while (setjmp(bc.brkpt))
                         if (isbreak)
                                 goto broken;
+                /* Restore areanum value. It may be incremented by execute()
+                 * below, and then "continue" may jump back to setjmp above */
+                areanum = a + 1;
+                freearea(areanum + 1);
                 brkset(&bc);
                 for (t1 = t->left; i-- && *wp != NULL;) {
                         setval(vp, *wp++);
@@ -2586,6 +2590,10 @@ static int execute(struct op *t, int *pin, int *pout, int no_fork)
                 while (setjmp(bc.brkpt))
                         if (isbreak)
                                 goto broken;
+                /* Restore areanum value. It may be incremented by execute()
+                 * below, and then "continue" may jump back to setjmp above */
+                areanum = a + 1;
+                freearea(areanum + 1);
                 brkset(&bc);
                 t1 = t->left;
                 while ((execute(t1, pin, pout, /* no_fork: */ 0) == 0) == (t->op_type == TWHILE))
diff --git a/shell/msh_test/msh-execution/many_continues.right b/shell/msh_test/msh-execution/many_continues.right
new file mode 100644
index 000000000..d86bac9de
--- /dev/null
+++ b/shell/msh_test/msh-execution/many_continues.right
@@ -0,0 +1 @@
+OK
diff --git a/shell/msh_test/msh-execution/many_continues.tests b/shell/msh_test/msh-execution/many_continues.tests
new file mode 100755
index 000000000..86c729abc
--- /dev/null
+++ b/shell/msh_test/msh-execution/many_continues.tests
@@ -0,0 +1,15 @@
+if test $# = 0; then
+    # Child will kill us in 1 second
+    "$THIS_SH" "$0" $$ &
+
+    # Loop many, many times
+    trap 'echo OK; exit 0' 15
+    while true; do
+        continue
+    done
+    echo BAD
+    exit 1
+fi
+
+sleep 1
+kill $1